#include <iostream>
#include <vector>
using namespace std;
vector<int> searchRange(vector<int> &nums, int target)
{
    // 处理边界情况
    if (nums.size() == 0)
        return {-1, -1};
    int begin = 0;
    // 1. 二分左端点
    int left = 0, right = nums.size() - 1;
    while (left < right)
    {
        int mid = left + (right - left) / 2;
        if (nums[mid] < target)
            left = mid + 1;
        else
            right = mid;
    }
    // 判断是否有结果
    if (nums[left] != target)
        return {-1, -1};
    else
        begin = left; // 标记一下左端点
    // 2. 二分右端点
    left = 0, right = nums.size() - 1;
    while (left < right)
    {
        int mid = left + (right - left + 1) / 2;
        if (nums[mid] <= target)
            left = mid;
        else
            right = mid - 1;
    }
    return {begin, right};
}